Somali pirates have captured more than 30 vessels this year, but the Sirius Star is their most ambitious attack yet. As their prizes become ever larger, the consequences will be felt by Western consumers, for these attacks are now a serious threat to international trade.

Last month I wrote a paper giving warning of the possibility of an attack on an oil tanker and of the consequences if international shipping began to react, avoiding the route via the Gulf of Aden and the Suez Canal and instead going around the Cape of Good Hope.

The longer route would add up to three weeks to the delivery of goods from Asia and of oil and gas from the Middle East to European markets. Someone will have to pay for that extra time – very probably the consumer. For Europe and the eastern seaboard of America, this inflation is a real possibility.

About 13 per cent of Middle Eastern oil and gas passes the Somali coast – oil prices have already risen after this most recent attack. It had been assumed that the pirates could capture only ships that were slow and low; the Sirius Star is neither. Companies with larger ships will see that the criminals are making the eastern Indian Ocean highly dangerous.

The pirates have reinvested their takings – now averaging well over $1 million per captured ship – in faster boats, electronic devices such as satellite phones, and powerful weapons. As their equipment improves they have been able to push farther out into the ocean and threaten ever more important vessels. The international response has had no impact on the growth of piracy in Somalia. The ransoms keep rising – and for many young Somalis with few other prospects the thought of military intervention is little deterrent.

For shipping companies, the question will be the possible loss of cargo, ships, time, ransom money and the lives of crew versus the fuel costs of sailing around the Cape. It is not hard to see that the argument is shifting towards the longer route.

Egypt receives very large sums from ships passing through the Suez Canal and the loss of that revenue would be painful. Mombasa is the major port for bringing goods into East and Central Africa. If companies felt that sailing there could become too dangerous, the effects on the Kenyan economy and on East Africa could be disastrous.

As pirates become bolder and use more powerful weapons, an oil tanker could be set on fire, sunk or forced ashore, any of which could result in marine and bird life being devastated for years.

Roger Middleton is a consultant researcher for the Africa Programme at Chatham House and author of Piracy in Somalia: Threatening Global Trade, Feeding Local Wars

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